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Subject: Re: Keyboard regression by intel-vbtn
To:     "Limonciello, Mario" <Mario.Limonciello@dell.com>,
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From:   Hans de Goede <hdegoede@redhat.com>
Message-ID: <55e021b7-5e1b-986b-07ec-279398570e40@redhat.com>
Date:   Tue, 29 Sep 2020 14:54:25 +0200
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Hi,

On 9/29/20 2:27 PM, Limonciello, Mario wrote:
>> I'm afraid that the only answer which I have to these questions
>> is not helpful, but in my experience it is true: "firmware sucks".
> 
> So FWIW there is a Dell 2-in-1 that has been conflated into this same issue.
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1822394

That is what a somewhat old kernel (5.0.0) which I guess may
lack your fix to check the chassis-type.

Interesting that this actually is a 2-in-1 though.

Also interesting that according to the reporter this was
triggered by a BIOS update.

If you by any chance can provide an acpidump with both the
1.2.0 and 1.4.0 BIOS versions that would be very interesting.

> Something that is confusing to me is that on the Windows side all these
> machines use the same Intel driver for this infrastructure no matter the
> OEM.
> So they can't possibly be putting in quirk specific stuff in the driver side
> can they?
> 
> It has to make you wonder if some baseline assumptions made in the
> driver early on around tablet mode support are completely false.

I'm not saying your wrong. If you can get Intel to provide
us with some documentation, or Windows driver source code
for this, then that would be great.

AFAICT the Linux driver currently is entirely based on
reverse engineering.

Regards,

Hans